https://github.com/aarontravass/block-transactions-index

https://github.com/aarontravass/block-transactions-index

Last synced: 22 days ago
JSON representation

• Host: GitHub
• URL: https://github.com/aarontravass/block-transactions-index
• Owner: aarontravass
• Created: 2024-04-22T21:56:55.000Z (7 months ago)
• Default Branch: master
• Last Pushed: 2024-04-23T05:23:26.000Z (7 months ago)
• Last Synced: 2024-10-08T02:42:37.235Z (about 1 month ago)
• Language: Python
• Size: 19.5 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

README

        
# Relayer Coding Challenge

### Part 1 Solution

For part 1, install all packages in requirements.txt and run the following in the current directory

```commandline

python .\index.py   18908800-18909050

```

Replace `` and `` with the values given in the email. (Hidden from public view due to spam)

The Python program uses the following packages

1. requests

2. sqlalchemy

`requests` is used for making HTTP calls and `sqlalchemy` is the ORM.

We first save all blocks to memory and then persist them in the DB.  

### Part 2 Solution

The following SQL statement will fetch the block with max volume:

```sql

SELECT SUM(('x'|| LPAD(SUBSTRING(VALUE, 3, LENGTH(VALUE)), 16, '0')):: BIT(64):: BIGINT) AS volume, 

('x'|| LPAD(SUBSTRING("Transaction"."blockNumber", 3, LENGTH("Transaction"."blockNumber")), 16, '0')):: BIT(64):: BIGINT AS "intBlockNumber"

FROM "Transaction"

INNER JOIN "Block" ON "Block"."blockNumber" = "Transaction"."blockNumber"

WHERE 

"timestamp" >= EXTRACT(EPOCH FROM TIMESTAMP '2024-01-01 00:00:00')*1000 AND 

"timestamp" <= EXTRACT(EPOCH FROM TIMESTAMP '2024-01-01 00:30:00')*1000

GROUP BY "intBlockNumber"

ORDER BY "volume" DESC

LIMIT 1

```

The sql first converts all value to bigint and then uses `sum` as an aggregate function, thus allowing us to perform group by clause on the `blockNumber` column.

We order by the `volume` and then take the first row.

The solution is 

 Volume               | Block Number 

----------------------|--------------

 53883433384695265018 | 18908973     

## Tests

Pytest is used for unit testing. Run `python tests/index.py` to run the test suite.